JP2002244423A - Image forming device and developer quantity detection system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device and a developer quantity detection system, by which a user is informed of the same developer quantity at any time while neglecting the variation of the detection values detected by a developer quantity detector when a device is a new one or at an initial using stage so that the user may not feel uneasy. SOLUTION: In the case of detecting the developer quantity by using the detection value detected by a developer quantity detecting means, it is unconditionally judged that a developer container is filled with the developer in the case the used developer quantity is small in the developer container, and it is displayed that 100% of the developer remains.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus, and more particularly to an electrophotographic image forming apparatus having a process cartridge and a developer amount detecting system.

Here, as an electrophotographic image forming apparatus,
For example, an electrophotographic copying machine, an electrophotographic printer (for example,
LED printers, laser beam printers, etc.), and electrophotographic facsimile machines.

A process cartridge is a cartridge in which at least one of a charging unit, a developing unit, and a cleaning unit and an electrophotographic photosensitive member are integrally formed into a cartridge, and this cartridge is detachably mountable to an electrophotographic image forming apparatus main body. Or a cartridge in which at least the developing means and the electrophotographic photosensitive member are integrally formed, and this cartridge is detachable from the main body of the electrophotographic image forming apparatus.

[0004]

2. Description of the Related Art Conventionally, in an electrophotographic image forming apparatus using an electrophotographic image forming process, an electrophotographic photosensitive member and a process means acting on the electrophotographic photosensitive member are integrated into a cartridge, and this cartridge can be attached to and detached from an image forming apparatus main body. Is widely adopted. In such an electrophotographic image forming apparatus of the process cartridge type, it is required that the user himself replaces the cartridge. Therefore, means for notifying the user when the developer is consumed, that is, a developer amount detecting device is required.

Conventionally, a developer amount detecting device has two electrode rods in a developer container of a developing means, and detects a change in capacitance between the two electrode rods to detect the presence or absence of the developer. There is something that detects Also, Japanese Patent Application Laid-Open No. Hei 5-100571 discloses that
In place of the two electrode rods, there is provided a developer detecting electrode member in which two parallel electrodes arranged on the same plane in parallel at a predetermined interval are combined with each other in an uneven shape. Disclosed is a developer amount detection device installed on a lower surface of a developer container. In this apparatus, a change in capacitance between parallel electrodes installed in a planar state is detected to detect the remaining amount of the developer.

The above-described developer amount detecting device detects the presence or absence of the developer in the developer container, and detects that the amount of the developer is small immediately before the developer is used up.

On the other hand, if the remaining amount of the developer in the developer container can be sequentially detected, it becomes possible for the user to know the use condition of the developer, and it is possible to prepare a new process cartridge at the time of replacement. Yes, very convenient for users.

Japanese Patent Laid-Open Publication No. Hei 10-303345 discloses that the amount of developer by a developer detecting electrode member in which two parallel electrodes arranged on the same plane in parallel at a predetermined interval are combined in an uneven shape. Sensing devices have been proposed. By arranging the detecting member on the end face or the bottom face of the developer container and detecting a change in the capacitance between the parallel electrodes, the amount of the developer can be sequentially detected.

Further, the remaining amount of the developer detected by the above method is displayed on a display unit of the image forming apparatus or on a screen of a computer connected to the image forming apparatus by displaying a numerical value such as% or a graphical bar. In addition, the user is notified of the remaining amount of the developer one by one.

[0010]

However, in the above-mentioned conventional example, the variation of the elements of the remaining amount detecting circuit in the developer sequential detecting device, the error of the mounting position of the device, and the developer in the developer container. Due to bias or the like, the detected value of the developer amount differs for each individual.

For example, in a new process cartridge, the developer amount should be full (100%), but it may be a value other than 100% due to the variation in the detection value of the developer amount sequential detection device. In particular, when the detected value is less than 100%, if the detected value is notified to the user as it is, the developer amount is displayed less than 100% in spite of a new process cartridge, which may confuse the user. There was such a problem.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an image in which a developer amount is always reported at the same value ignoring a variation in a detected value of a developer amount detecting device in a new or early use, so that a user is not anxious. An object of the present invention is to provide a forming apparatus and a developer amount detecting system.

[0013]

The above object is achieved by an image forming apparatus and a developer amount detecting system according to the present invention. In summary, according to the first aspect of the present invention, in an image forming apparatus which develops a latent image formed on an image carrier using a developer to form an image on a recording medium, the image on which the latent image is formed A developer carrier for supplying the developer to the carrier, a developer container for containing the developer to be supplied to the developer carrier, and a sensor for detecting a remaining amount of the developer contained in the developer container. Developer amount detection means, storage means installed in the developer container for storing information, communication means for reading and writing information stored by the storage means, and a usage amount of the developer container A determination unit for unconditionally determining that the developer is full when the number is small, the image forming apparatus is provided.

According to an embodiment of the first invention, the developer container is detachable from the image forming apparatus.
According to another embodiment, at least the developer container,
The developing device is an integral developing device with the developer carrier, and is detachable from the image forming apparatus. According to still another embodiment, at least the image carrier, the developer carrier, the developer container, and the developer amount detection unit are an integrated process cartridge, and the It is removable.

According to another embodiment of the first aspect of the present invention, the information stored in the storage means includes at least information indicating an amount of use of the developer container and a developing amount detected by the developer amount detecting means. Dosage. Here, the information indicating the usage amount of the developer container is the cumulative rotation time of the photosensitive drum,
It may be the cumulative number of prints, the cumulative application time of the charging bias, or the cumulative exposure time of the laser.

According to another embodiment of the first invention, the amount of developer detected by the developer amount detecting means is stored in the storage means irrespective of the used amount of the developer container.

According to another embodiment of the first invention, the developer amount detected by the developer amount detecting means is stored in the storage means only when the used amount of the developer container is larger than a predetermined value. Is done.

According to still another embodiment of the first invention, the developing means installed in the image forming apparatus or displayed on the display means connected to the image forming apparatus is determined by the determining means. Report the dosage.

According to the second aspect of the present invention, in the developer amount detecting system for detecting the amount of the developer in the developer container for storing the developer, the detection value detected by the developer amount detecting means is used. In detecting a developer amount, a developer amount detection system is provided in which, when the used amount of the developer container is small, the developer is unconditionally determined to be full.

According to one embodiment of the present invention, the developer amount detecting means includes: (a) a pair of electrodes on an input side and an output side formed on a same plane in parallel with a predetermined interval. An electrode member for detecting the capacitance between the electrodes,
A first detection member having a measurement-side electrode in contact with the developer and a reference electrode not in contact with the developer; and (b) a conductive member, which detects a capacitance between the first carrier and the developer carrier. And the first detection member detects the amount of developer from the start of use of the developer container to the middle of use of the developer container, and then the developer is detected by the second detection member. Detect the amount of

According to another embodiment of the second invention,
The developer amount detection system has a means for displaying the detected amount of developer or a communication means for transmitting the detected amount of developer to the display means.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an image forming apparatus and a developer amount detecting system according to the present invention will be described in detail with reference to the drawings.

Embodiment 1 (Description of Process Cartridge and Image Forming Apparatus Main Body)
Hereinafter, an image forming apparatus according to the present invention will be described in detail with reference to the drawings.

First, an embodiment of an electrophotographic image forming apparatus to which a process cartridge A constructed according to the present invention can be mounted will be described with reference to FIG. In the present embodiment, the electrophotographic image forming apparatus is an electrophotographic laser beam printer B, and a recording medium such as a recording paper, an OHP sheet,
An image is formed on a cloth or the like.

The process cartridge A, which will be described later in detail with reference to FIG. 2, is a drum-shaped electrophotographic photosensitive member, that is, a photosensitive drum 1 and a photosensitive drum 1 for uniformly charging the surface of the photosensitive drum 1. Charging means 2 and a roller-shaped developer carrier as a developing means disposed opposite to the photosensitive drum 1, that is, a developing roller 3, and a developing container D made of a resin such as polystyrene connected to the developing roller 3. And a developer container E as a developer accommodating portion for accommodating a developer, and a cleaning container C having a cleaning means 8 are integrally formed.

A laser beam printer B, which is an image forming apparatus, has a laser scanner 4 for irradiating a laser beam corresponding to image information above a process cartridge A.
And a transfer unit 5 facing the photosensitive drum 1 below.
Are arranged. In the above configuration, image formation is performed as follows.

First, the photosensitive drum 1 is uniformly charged by the charging means 2, and its surface is scanned and exposed by a laser beam irradiated from the laser scanner 4, thereby forming an electrostatic latent image of target image information. The electrostatic latent image is transferred to the developing roller 3
The developer T in the developing container D adheres and is visualized as an image. In this example, an insulating magnetic one-component developer (toner) was used as the developer. The developer is not limited to this, and may be, for example, a magnetic developer or an insulating magnetic developer.

The image on the photosensitive drum 1 is stored in a paper cassette 6
Is transferred by the transfer means 5 to the recording paper S fed and conveyed from the printer. The recording sheet S passes through the fixing means 7 to fix the image on the recording sheet S, and is discharged to a discharge tray 9 outside the main body. After transferring the developer image onto the recording paper S, the developer T remaining on the photosensitive drum 1 is removed by the cleaning unit 8 and collected in the cleaning container C.

Further, the process cartridge A includes
As shown in FIG. 1, a memory unit 100 as a storage means is mounted. In this embodiment, the memory unit 100
Are mounted on the developer container E, that is, on the side surface of the process cartridge A.

(Overall System Configuration) Next, the system configuration of the image forming apparatus of this embodiment will be described with reference to the system block diagram shown in FIG.

An engine controller 50 for performing system control of the entire image forming apparatus is provided, and a central processing unit (CPU) (not shown) is disposed inside the engine controller 50. A series of system processes of the image forming apparatus are performed according to a program stored in advance in the central processing unit.

The high voltage power supply 51 includes a charging bias in which an AC voltage is superimposed on a DC voltage supplied to the charging means 2, a developing bias in which an AC voltage is superimposed on a DC voltage supplied to the developing roller 3, and a DC voltage which is supplied to the transfer means 5. And a fixing bias which is a DC voltage supplied to the fixing unit 7.

Further, according to the system configuration of this embodiment,
A driving unit 52 including a motor, a solenoid, and the like provided in the apparatus, a sensor group 53 provided at a predetermined position inside the image forming apparatus, a display unit 54 for displaying a state of the apparatus, a developer detecting member in the process cartridge A The capacitance of the
First and second developer amount detecting devices 55 for detecting the amount of developer
A and 55B are provided, and are controlled by the engine controller 50. In addition, the engine controller 50 includes:
Memory unit 10 mounted on process cartridge
0 is connected to a memory control circuit 56 for performing control of 0.

(Explanation of Memory Unit) In this embodiment, as shown in FIG.
The memory unit 100 and the memory control circuit 56 mounted on the side of the device will be described.

The memory unit 100 incorporates a nonvolatile storage element (EEPR0M) 41 therein, and performs data communication with the image forming apparatus main body to write and read data in the storage element 41. It can be performed. All data communication controls are performed by the memory control circuit 5
6 is performed. Data communication is performed in a non-contact manner by magnetic coupling between an antenna 42 provided in the memory unit 100 and an antenna 43 provided in the image forming apparatus main body. When the process cartridge A is mounted on the laser printer B, the memory unit 100 and the memory control circuit 56 are arranged so that the antenna 42 of the memory unit 100 and the antenna 43 provided on the laser printer 100 are close to each other and are in a communicable state. is set up. Then, the controller 44 in the memory unit 100 and the controller 45 in the memory control circuit 56 control the respective communication interface circuits 46 and 47 to transmit and receive data via the antennas 42 and 43, so that the memory element 41 Is read and written.

A power supply circuit 48 is provided inside the memory unit 100, and all the DC power used inside is supplied from the power supply circuit 48. The power supply circuit 48 generates a DC voltage by rectifying a current generated in the two antennas 42 and 43 by magnetic coupling. The memory unit 100 stores information about the process cartridge A, such as the cumulative rotation time of the photosensitive drum in the process cartridge and the remaining amount of the developer.

(Configuration of Process Cartridge) FIG.
FIG. 4 is an exploded perspective view of the process cartridge A of the present embodiment, and FIG.

In FIG. 2, a process cartridge A of this embodiment includes a developer container E containing a developer, a developing container D holding a developing roller 3 as a developing member, a photosensitive drum 1 and a cleaning means 8. Cleaning container C, a developer container E, and side covers 10 and 11 for holding the cleaning container C. The containers are combined to form a cartridge.

In FIG. 4, the developer container E has a horizontally long shape in order to cope with an increase in capacity, and the bottom surface of the developer container E has three concave shapes. Three transport members 12, 13, which are driven by a motor of a main body not shown,
Numeral 14 corresponds to a concave portion of the developer container E, and is provided with stirring blade members 12 a, 13 a provided on the conveying members 12, 13, 14.
The developer T is transported to the developing container D by a and 14a.

By making the developer container E horizontally long, the self-weight of the developer T can be reduced, so that fading, deterioration of the developer, and increase in stirring torque can be reduced.

A resin sheet member such as polyethylene terephthalate or polyphenylene sulfide is used for the stirring blade members 12a to 14a, and stirs and transports the developer T. The rotation radius of the tip of each of the stirring blade members 12a to 14a is larger than the radius of the bottom of the developer container E, and the tip rubs against the bottom of the developer container E. Thereby,
Developer T without leaving developer T on the bottom of developer container E
Is being transported horizontally.

(Configuration of Developer Amount Detecting Member) As shown in FIG. 4, according to the present embodiment, a first detecting member 20 and a second detecting member 21 are provided for sequentially detecting the amount of developer. Have been. The first detection member 20 is used to detect a region where the developer T is large, and the second detection member 21 is used to detect a region where the developer T is small.

More specifically, the first detecting member 20 detects the amount of developer from about 50% to about 10% from the initial stage of use, and the second detecting member 21 detects about 50% to 10% of the developer. % Until the developer runs out. Both the first detection member 20 and the second detection member 21 measure the amount of the developer by the capacitance.

FIGS. 5A to 5D show how the amount of the developer changes, and FIG. 6 shows the relationship between the amount of the developer and the capacitance. In this embodiment, it is assumed that the transfer from the first detection member 20 to the second detection member 21 is performed around the time when the developer amount becomes about 20%. (A) to (d) of FIG. 5 and graphs (a) to (d) shown in FIG. 6 correspond to each other. (A) When the developer amount is 100%, the first detection member 2
Both the 0 and the second detection members 21 are buried in the developer.
At this time, the output of the first detection member 20 is X2. (B) As the developer is gradually consumed, the amount of the developer in the detection area of the first detection member 20 changes. The output also changes as the area of the developer in contact with the surface of the first detection member 20 changes. At this time, the first
Is X3. (C) The second detection member 21 starts operating around the time when the amount of the developer becomes about 20%. At this time, the output of the second detection member 21 is Y2. (D) Detection is performed until the developer becomes 0%. At this time, the output of the second detection member 21 is Y1. Therefore, it is possible to sequentially detect all areas from the beginning to the end of using the process cartridge A.

(Principle and Structure of First Detecting Member) Next, the operating principle of the first and second detecting members 20 and 21 will be described. First, the first detecting member 20 is shown in FIG. FIG. 8 is a view seen from the opposite side of FIG. 7, and FIG.
FIG. In FIG. 9, the first detection member 20
Has a measurement-side output electrode 22a, a reference-side output electrode 22c, and a common input electrode 22b. The combination of the measurement-side output electrode 22a and the common input electrode 22b is referred to as a measurement electrode 20a,
The combination of the reference side output electrode 22c and the common input electrode 22b is referred to as a reference electrode 20b.

7 and 8, the measuring electrode 20a is arranged at a position such as the inner side surface of the developer container E that comes into contact with the developer T. Electrodes 22a, 22 which are paired electrodes
By measuring the capacitance between b, the change in the area of the developer that is in contact with the electrode surface can be detected, and the amount of the developer in the developer container E can be known. That is, since the developer T has a higher dielectric constant than air, if the area of the surface of the first detection member 20 that the developer T is touching changes, the electrode 22
The capacitance between a and 22b changes.

The reference electrode 20b is arranged at a position in the developer container E but not in contact with the developer T, so that a change in capacitance when environmental conditions are changed is the same as that of the measurement electrode 20a. Designed to. In this embodiment, the measuring electrode 20
a and the electrode pattern of the reference electrode 20b have the same shape. Therefore, by subtracting the value of the capacitance of the reference electrode 20b from the value of the capacitance of the measurement electrode 20a, it can be regarded that there is no change in the capacitance due to environmental conditions, and the detection accuracy can be improved. Becomes possible.

As shown in FIG. 9, the first detecting member 20
Preferably, a measurement electrode 20a and a reference electrode 20b are provided on one surface of a single bendable substrate such as a flexible printed circuit board, and are folded and arranged in the developer container E. The first detection member 20 uses an adhesive such as a double-sided tape, and fixes the edge or the entire back surface to the developer container E so that the developer does not enter the back side of the measurement electrode 20a.

(Arrangement of First Detecting Member) FIG. 10 is a perspective view of the developer container E. The developer container E is provided with three transport members 12, 13, and 14, but the first detection member 20 is located at a position where the developer T is sent to an operation area of a second detection member 21 described later. Are arranged in a region where the conveying member 13 closest to the developing roller 3 is arranged.

That is, in this embodiment, the first detecting member 20
Represents the developer T contained in the developer container E.
Is arranged upstream of the second detection member 21 in the developer supply direction for supplying the developer in the direction in which the developing roller 3 is provided.

Further, the first detecting member 20 is
The first detection member 20 is disposed on the driving side wall in the developer container E such that the first detection member 20 surrounds the axis. By arranging the first detection member 20 at this position, it is possible to reduce the area of the first detection member 20 while realizing sequential detection, thereby reducing component costs. Further, the effect of the developing bias can be reduced by separating the developing roller from the developing roller 3.

Since the sensitivity of the first detecting member 20 in the vicinity of the surface of the detecting member is extremely high, providing the surface wiping member 13b as a means for removing the developer on the surface is effective in increasing the detection accuracy. . When the surface wiping member 13b is provided, the developer transport member 13b is provided for simplifying the configuration.
It is preferable to provide a wiping member 13b on the surface. Also,
At this time, the first detection member 20 is disposed within a range in which the wiping member 13b functions, corresponding to the developer stirring area.

(Structure of Wiping Member) In this embodiment, as shown in FIG. 10, the developer conveying member 13 is provided with the surface wiping member 13b of the first detecting member 20.
The wiping member 13b is provided only on the transport member 13 at the position where the first detection member 20 is provided.

The developer conveying member 13 includes a stirring rod member 13.
c, a stirring blade member 13a, a stirring blade holding member 13d, and a wiping member 13b. The stirring bar member 13c is rotatably supported by the developer container E. Stirring blade member 13
“a” is pressed against and fixed to the stirring rod member 13c by the stirring blade holder 13d. Stirring blade holder 13d
Is formed of sheet metal or resin, and is fixed to the stirring rod 13c by heat staking, ultrasonic welding, bonding or the like. The wiping member 13b is also fixed by a stirring blade retainer 13d similarly to the stirring blade 13a. The stirring blade 13a is formed of a resin material such as polyethylene terephthalate or polyphenylene sulfide. Wiping member 13b
For example, a sheet member made of a resin such as polyethylene terephthalate or polyphenylene sulfide can be used, or a rubber or foam member can be used. That is, any material can be used for the wiping member 13b as long as the material is suitable for wiping the surface of the first detection member 20.

FIG. 11 shows the first detecting member 20 in a state where the developer has been consumed to some extent. The attached developer T 'exists above the developer surface. If the adhered developer T ′ is present, the capacitance of the measurement electrode 20a of the first detection member 20 increases, which causes a variation.

Therefore, as described above, the wiping member 13
By wiping the first measurement electrode 20a with b, the developer adhering above the developer surface can be removed, and the detection accuracy can be improved.

(Method of Detecting Capacitance of First Detecting Member) Next, a method of detecting capacitance of the first detecting member 20 will be described in detail. According to the developer amount detecting system of the present embodiment, the first detecting member 20 as the first capacitance generating member
Is connected to the first developer amount detecting device 55A shown in FIG. 14, and the capacitance of the first detecting member 20 is detected.

FIG. 16 is a diagram showing the internal circuit configuration of the developer amount detecting device 55A. The terminal 59 is connected to the electrode 22b of the first detection member 20 via an electric contact (not shown) provided with a contact portion exposed from the cartridge frame, and supplies a clock CLK1 for detecting the amount of developer. Output. The clock CLK1 is generated by the resistor 62, the resistor 63, and the transistor 64. The signal CLKA is a clock output from the engine controller 50 and is a rectangular wave having a frequency fc = 50 KHz and a duty = 50%.
The clock CLKA has an amplitude =
It is amplified to Vc and output from terminal 59.

The terminal 57 is connected to the measurement-side output electrode 22a of the first detecting member 20 via an electric contact (not shown) whose contact portion is exposed from the cartridge frame. When the clock output from the terminal 59 is applied to the measurement-side output electrode 22b, the electrode 22a and the electrode 22b
The alternating current I12 flows to the terminal 57 due to the capacitance Ct therebetween. Here, the magnitude of the alternating current I12 is a value corresponding to the capacitance value Ct. The AC current I12 is rectified by diodes 69 and 67 provided at an input portion of the terminal 57, and the rectified current I13 is input to an integration circuit including an operational amplifier 72, a resistor 75, and a capacitor. Here, I13 is a current of a one-way component of the current I12 (hereinafter, referred to as “half-wave current”).

On the other hand, the terminal 58 is an electric contact (not shown) provided with a contact portion exposed from the cartridge frame.
Is connected to the reference-side output electrode 22c of the first detection member 20 via the. With the clock output from the terminal 59, a current I14 having a magnitude corresponding to the capacitance Cr between the electrode 22b and the electrode 22c flows through the terminal 59. Current I1
4 is rectified by diodes 68 and 70 set in the opposite direction to the input section of the terminal 57, and the current I15 is input to the integration circuit. The current I14 is a half-wave current having a polarity opposite to that of the current I13. The current I13 and the current I15 input to the integration circuit are integrated, and I13 and I
A DC voltage Vd1 corresponding to the average value of the 15 total currents is generated. Assuming that the resistance value of the resistor 75 is Rs1, the voltage Vd1
Can be approximated by the following equation. Vd1 = Rs1 × fc × Vc × (Ct−Cr) (Equation 1) On the other hand, a predetermined reference voltage Vt is applied to the positive input of the operational amplifier 72.
1 is input, and the output of the operational amplifier 72 has the following characteristics. Vs1 = Vt1−Rs1 × fc × Vc × (Ct−Cr) (Expression 2) As shown in the above expression, the output voltage Vs of the operational amplifier 72
1 is the difference between the capacitance between the electrodes 22a and 22b on the measurement electrode 20a side and the capacitance between the electrodes 22c and 22b on the reference electrode 20b side, that is, a voltage value according to the amount of the developer in the process cartridge A. Becomes The output Vs1 of the operational amplifier is output from the output terminal 60.

The terminal 60 is connected to an analog / digital conversion terminal of the central processing unit in the engine controller 50. The voltage level Vs1 corresponding to the developer amount is converted into digital data, and is further converted into a developer amount T1 in the process cartridge A by comparing with a conversion table stored in the engine controller 50 in advance.

The conversion table shows the relationship between the voltage level converted into digital data and the amount of developer. The developer amount T1 obtained from this is represented by 100% when the developer amount is full when not in use and 0% when the developer amount is completely used, but the remaining weight of the developer is expressed as%. Or the like, as long as the remaining amount of the developer can be known.

(Configuration and Arrangement of Second Detecting Member) FIG.
Shows a cross section of the developer container E, and FIG.
FIG. 5 is a diagram of the developer container E viewed from below. The second detection member 21 is provided outside the developer container E, and further has a cover member 23 outside.

The second detecting member 21 is formed by sheet metal over the entire longitudinal area along the concave shape of the bottom surface of the developer container E. Developing roller 3 and developer regulating member supporting member 1
Reference numeral 5 is electrically connected, and measures a change in capacitance between the second detection member 21, the developing roller 3, and the developer regulating member support member 15 to detect the amount of developer.

The second detecting member 21 is fixed to the concave portion of the developer container E closest to the developing roller 3 outside the developer container E by caulking or bonding. Second detection member 2
By providing 1 outside the developer container E, there is no need to pass the wiring to the contact point connected to the image forming apparatus main body into the developer container E, so that there is no fear of developer leakage.

(Method of Detecting Capacitance of Second Detecting Member) Next, a method of detecting capacitance of the second detecting member 20 will be described in detail. According to the developer amount detection system of the present embodiment, the second detection member 21 as the second capacitance generation unit
Is connected to the second developer amount detecting device 55B in FIG. 14, and the capacitance value between the second detecting member 21, the developing roller 3, and the developer regulating member supporting member 15 is detected.

FIG. 17 is an internal circuit configuration diagram of the developer amount detecting device 55B. Terminal 80 is an electrical contact (not shown)
Is connected to the second detection member 21 via the. When the developing AC bias generated by the high-voltage power supply 51 is applied to the developing roller 3, the AC is applied to the terminal 80 by the second detecting member 21 and the capacitance Cs between the developing roller 3 and the developer regulating member supporting member 15. The current I1 flows. Here, the current I1
Is a value corresponding to the capacitance value Cs. Current I1
Are diodes 86 and 8 provided at the input of terminal 80.
The rectified current I2 is input to an integration circuit including an operational amplifier 91, a resistor 93, and a capacitor 94. Here, the current I2 is a half-wave current of the current I1.

On the other hand, the terminal 81 is connected to a developing bias output section (not shown) inside the high voltage power supply 51. That is, the same developing bias as that of the developing roller 3 is applied to the terminal 81. A capacitor 85 having a capacitance Ck is connected to an input portion of the terminal 81. When a developing AC bias is applied, an AC current I3 having a magnitude corresponding to the capacitance Ck is applied.
Flows.

The capacitor 85 is a reference capacitor serving as a measurement reference. The capacitance value Ck is determined by the second detecting member 21 when there is no developer in the process cartridge A, the developing roller 3 and the developer regulating member supporting member. The capacitance value is set to between 15 and 15. The current I13 is rectified by diodes 87 and 89 set in the opposite direction to the input of the terminal 81, and the current I4 is input to the integration circuit. The current I4 is a half-wave current having a polarity opposite to that of the current I2. The current I2 and the current I4 input to the integration circuit are integrated and the resistance 93
Generates a DC voltage Vd2 corresponding to the average value of the total current of 12 and 14. The frequency of the developing AC bias is f
If d, the amplitude is VP, and the resistance of the resistance 93 is Rs2, Vd2 can be approximated by the following equation. Vdd = Rs2 × fd × Vp × (Cs−Ck) (Equation 3) On the other hand, a predetermined reference voltage Vt is applied to the positive input of the operational amplifier 91.
2 is input, and the output of the operational amplifier 91 has the following characteristics. Vs2 = Vt2−Rs2 × fd × Vp × (Cs−Ck) (Equation 4) As shown in the above equation, the output voltage Vs2 of the operational amplifier
Is the difference between the electrostatic capacitance of the reference capacitor 85 and the voltage value corresponding to the amount of the developer in the process cartridge A, between the second detecting member 21 and the developing roller 3 and between the developer regulating member supporting member 15. . The output Vs2 of the operational amplifier 91 is output from the output terminal 82. The terminal 82 is connected to an analog / digital conversion terminal of the central processing unit in the engine controller 50.

The voltage level Vs2 corresponding to the developer amount is converted into digital data, and is further converted into a developer amount T2 in the process cartridge A by comparing with a conversion table stored in the engine controller 50 in advance.
The developer amount T2 is a value represented by% similarly to the developer amount T1 detected by the first detection member 20.

The developer amount T1 detected by the first detection member 20 and the developer amount T2 detected by the second detection member 21
Is compared inside the engine controller 50, and the value of the developer amount T1 or the developer amount T2 is determined as the developer amount of the process cartridge. Then, by the control described later, the value of the developer amount T1 or the developer amount T2 is displayed on the display unit 54 to notify the user. Further, the detected value of the detected amount of the developer is stored in the process cartridge memory unit 100.

The display section 54 may be a display provided in the main body of the image forming apparatus, or may be a display of a personal computer communicable by communication means of the main body of the image forming apparatus.

With the above configuration, the first detecting member 2
0, the second detection member 21 and the wiping member 13b are provided so that the remaining amount of the developer in the developer container E can be reduced according to the consumption of the developer in the developer container E from immediately after the use of the process cartridge to immediately before the developer runs out. The amount can be detected sequentially.

Next, a method of notifying a user of the amount of developer, which is a feature of the present invention, will be described.

A feature of the present embodiment is that when notifying the user of the amount of developer, information indicating the used amount of the developer container, for example, the amount of developer is considered in consideration of the accumulated rotation time of the photosensitive drum. It is.

The memory unit stores the cumulative rotation time of the photosensitive drum printed by the process cartridge. This updates the accumulated rotation time stored in the memory unit every time one print is performed or after a series of multiple prints are performed.

FIG. 18 shows a flowchart of the control in this embodiment. In the control having a plurality of steps (S), first, the developer amount is detected by the developer amount detecting device (step 101), and the detected value obtained for the developer amount in the memory unit is updated (step 101). 102). next,
The cumulative rotation time of the photosensitive drum in the memory unit is read (step 103), and is compared with a predetermined value (step 104). This predetermined value is a value that can be said to be a small amount of the process cartridge used, for example,
Set to seconds. This is because if the photosensitive drum is rotated for at least this time, the bias of the developer in the developer container is eliminated by the stirring means. If it is less than the predetermined value, the developer amount is changed to 100% irrespective of the detected value (step 105), and a notification is issued (step 106). If the accumulated rotation time is equal to or longer than the predetermined value, the detected developer amount value is notified to the user as it is (step 106).

Thus, when the used process cartridge is new or in the early stage of use, the amount of the developer is notified to be 100% irrespective of the value detected by the developer amount detecting device. Variations in the detected value due to the difference or the bias of the developer in the developer container can be ignored, and the user can be assured that the developer amount is always displayed as 100% in the initial stage of use.

Here, in this embodiment, the accumulated rotation time of the photosensitive drum is stored in the memory unit, and the value for informing the developer amount is determined based on the value. However, the present invention is not limited to the accumulated rotation time. It is sufficient if the amount of use of the process cartridge or the developer can be estimated, and for example, the cumulative number of prints, the cumulative application time of the charging bias, the cumulative exposure time of the laser, or the like may be used.

Further, in the above embodiment, the value of the developer amount in the memory unit is updated immediately after the detection of the developer amount. However, as shown in the flowchart of the modification of this embodiment shown in FIG. After the value of the developer amount to be notified is changed according to the accumulated rotation time (step 114), the developer amount may be updated (step 115). That is, the update of the developer amount stored in the memory unit can be performed regardless of the accumulated rotation time.

Embodiment 2 Hereinafter, a second embodiment of the present invention will be described. The configuration of this embodiment is the same as that of the first embodiment, and a detailed description is omitted. A feature of this embodiment is that the developer amount is not updated when the accumulated rotation time of the photosensitive drum stored in the memory unit is equal to or less than a predetermined value.

FIG. 20 shows a flowchart relating to the control of this embodiment. First, the developer amount is detected by the developer amount detection device (step 201). Next, the accumulated rotation time of the photosensitive drum stored in the memory unit is read (Step 202), and is compared with a predetermined value (Step 203). If the read cumulative rotation time is equal to or less than the predetermined value, the developer amount is set to 100 regardless of the detected value.
% (Step 204) and notify the user (step 206). If the value is equal to or more than the predetermined value, the developer amount stored in the memory unit is updated to the detected value (step 205), and the value is notified to the user (step 20).
6).

Accordingly, when the used process cartridge is new or is in the initial stage of use, it is not necessary to update the developer amount stored in the memory unit, and the developer amount notified to the user is not required. Is unconditionally set to 100%, the variation in the detection value by the developer amount detection device can be ignored. Furthermore, since the amount of the developer is always displayed as 100% in the early stage of use, the user is not confused.

Here, after the amount of the developer is detected, it is determined whether or not the amount of the developer in the memory unit is to be updated based on the accumulated rotation time. As described above, the amount of developer may be detected only when the cumulative rotation time is read in advance and the value is equal to or more than the predetermined value. This eliminates the need to perform the operation of detecting the amount of the developer when it is not necessary. That is, the control may be such that the developer amount in the memory unit is updated when the accumulated rotation time is equal to or more than the predetermined value, and is not updated when the accumulated rotation time is equal to or less than the predetermined value.

Third Embodiment In the first and second embodiments, the process cartridge A or the image forming apparatus provided with the process cartridge A has been described. However, the principle of the present invention described in the first and second embodiments is as follows. Photoconductor drum 1, charging means,
In a developing device provided with a developer container and a developer carrying member having a configuration excluding the cleaning unit 8, furthermore,
The same can be applied to a developer container.

That is, the developer container E and the developer amount detection system described in the first and second embodiments of the present invention are the same as the developer carrier and the developer container which are detachable from the image forming apparatus. The present invention is similarly applied to a developing device for developing an electrostatic latent image formed on an electrophotographic photosensitive member, and further to a developer container, and can achieve the same operation and effect.

[0087]

As described above, the image forming apparatus and the developer amount detecting system according to the present invention each include:
(A) In an image forming apparatus that develops a latent image formed on an image carrier using a developer to form an image on a recording medium,
A developer carrier for supplying the developer to the image carrier on which the latent image is formed, a developer container for containing the developer to be supplied to the developer carrier, and a residual developer contained in the developer container; A developer amount detecting unit for detecting the amount, a storage unit installed in the developer container for storing information, a communication unit for reading and writing information stored in the storage unit, and use of the developer container A determination unit that unconditionally determines that the developer is full when the amount is small,
(B) In a developer amount detection system that detects the amount of developer in a developer container that stores the developer, the developer amount is detected using the detection value detected by the developer amount detection unit. When the used amount of the developer container is small, the configuration is such that the developer is unconditionally determined to be full. Therefore, in the developer container, the developing device, or the process cartridge in the new or initial use, the toner in the developer container is When the usage amount is small, the user is notified that the developer amount is full, regardless of the detection value of the developer amount sequential detection device, and the variation in the detection value of the developer amount detection device is
In particular, it can be ignored in the early stage of use, and the developer amount is always reported at the same value, so that the user is not anxious.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of an electrophotographic image forming apparatus according to the present invention.

FIG. 2 is an exploded perspective view showing a configuration of a process cartridge according to the present invention.

FIG. 3 is a side view of the process cartridge according to the present invention for explaining the arrangement of the memory units.

FIG. 4 is a sectional view of a process cartridge according to the present invention.

FIG. 5 is a cross-sectional view of the developer container showing a state of developer consumption.

FIG. 6 is a graph showing a relationship between a developer amount and a capacitance in the developer amount detection device of the present invention.

FIG. 7 is a perspective view of a first detection member according to the present invention.

FIG. 8 is a perspective view of a first detection member according to the present invention.

FIG. 9 is a development view of a first detection member according to the present invention.

FIG. 10 is a perspective view of a developer container according to the present invention.

FIG. 11 is a perspective view showing an operation mode of the wiping member according to the present invention.

FIG. 12 is a sectional view of a process cartridge for explaining a second detection member according to the present invention.

FIG. 13 is a perspective view illustrating the location of the second detection member according to the present invention as viewed from below the process cartridge.

FIG. 14 is a system block diagram of the image forming apparatus according to the present invention.

FIG. 15 is a block diagram of a memory unit and a memory control circuit according to the present invention.

FIG. 16 is an internal circuit diagram of a first developer amount detecting device according to the present invention.

FIG. 17 is an internal circuit diagram of a second developer amount detecting device according to the present invention.

FIG. 18 is a flowchart of control according to the first embodiment of the present invention.

FIG. 19 is a flowchart of control in which the embodiment shown in FIG. 18 is changed.

FIG. 20 is a flowchart of control in a second embodiment of the present invention.

FIG. 21 is a flowchart of control in which the embodiment shown in FIG. 20 is modified.

[Explanation of symbols]

Reference Signs List A process cartridge B laser printer C cleaning container D developing container E developer container 1 electrophotographic photosensitive member (photosensitive drum) 2 charging means 3 developer carrying member (developing roller) 4 laser scanner 5 transfer means 10, 11 side cover 12 , 13, 14 Developer transport member 12 (a), 13 (a), 14 (a) Stirrer blade 13 (b) Wiping sheet 13 (c) Stirrer bar 13 (d) Stirrer blade holder 15 Developer regulating member support member Reference Signs List 20 first detection member 20a measurement electrode 20b reference electrode 21 second detection member 22a measurement-side output electrode of first detection member 22b common input electrode of first detection member 22c reference-side output electrode of first detection member 41 storage element (EEPROM) 50 engine controller 54 display unit 55A first developer amount detection device 55B second development The amount detection device 56 the memory control circuit 100 memory unit

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03G 21/00 386 G03G 15/00 556 F term (Reference) 2F014 AA10 AC07 EA10 2H027 DA06 DA07 DA38 DA45 DD02 DE04 DE07 EE08 EE10 EJ08 GB03 2H071 BA03 BA04 BA13 BA27 BA33 DA08 DA15 DA32 2H077 AA02 AB03 AB12 AB15 AB18 AC04 AD06 BA09 DA01 DA15 DA22 DA32 DA59 DB10 EA13

Claims (12)

[Claims] 1. An image forming apparatus which develops a latent image formed on an image carrier using a developer and forms an image on a recording medium, supplies a developer to the image carrier on which the latent image is formed. A developer carrying member, a developer container containing a developer to be supplied to the developer carrying member, a developer amount detecting unit for detecting a remaining amount of the developer contained in the developer container, A storage unit that is installed in the developer container and stores information; a communication unit that reads and writes information stored in the storage unit; and a developer that is unconditionally used when the usage amount of the developer container is small. A determination means for determining that the image forming apparatus is full. 2. The image forming apparatus according to claim 1, wherein the developer container is detachable from the image forming apparatus. 3. The image forming apparatus according to claim 1, wherein at least the developer container and the developer carrier are an integrated developing device, and are detachable from the image forming device. 4. A process cartridge in which at least the image carrier, the developer carrier, the developer container, and the developer amount detecting unit are integrated, and are detachable from the image forming apparatus. 2. The method according to claim 1, wherein
Image forming apparatus. 5. The information stored in the storage unit includes at least information indicating a usage amount of the developer container and a developer amount detected by the developer amount detection unit. Item 5. The image forming apparatus according to any one of Items 1 to 4. 6. The information indicating the used amount of the developer container,
6. The image forming apparatus according to claim 5, wherein the cumulative rotation time of the photosensitive drum, the cumulative number of prints, the cumulative application time of the charging bias, or the cumulative exposure time of the laser. 7. The storage device according to claim 1, wherein the developer amount detected by the developer amount detection unit is stored in the storage unit irrespective of a usage amount of the developer container. An image forming apparatus according to any of the above items. 8. The storage device according to claim 1, wherein the developer amount detected by the developer amount detection unit is stored only when the usage amount of the developer container is larger than a predetermined value. 7. The image forming apparatus according to any one of items 6. 9. A developer installed in the image forming apparatus or connected to the image forming apparatus to notify a display unit of the amount of the developer determined by the determining unit. An image forming apparatus according to any one of Items 1 to 8. 10. A developer amount detection system for detecting a developer amount in a developer container for storing a developer, wherein the developer amount is detected using a detection value detected by the developer amount detection means. When the used amount of the developer container is small, it is determined unconditionally that the developer is full. 11. The developer amount detecting means includes: (a) a pair of input and output electrodes formed on a same plane in parallel at a predetermined interval, and detects a capacitance between the electrodes; A first detecting member having a measurement side electrode in contact with the developer and a reference electrode not in contact with the developer,
(B) a second detection member, which is made of a conductive member, and detects a capacitance between the developer container and the developer container. The developer amount detection system according to claim 10, wherein the amount is detected by the first detection member, and then the amount of the developer is detected by the second detection member. 12. The developer amount detection system according to claim 1, further comprising: means for displaying the detected amount of developer, or communication means for transmitting the detected amount of developer to the display means. Item 10. The developer amount detection system according to Item 10 or 11.